Amphibious vehicle transmission

Abstract

An amphibious vehicle has retractable road wheels to allow planing over water. Power to the road wheels is disconnected automatically as the wheels are retracted. This may be achieved through a cable attached to a suspension rocker arm to disconnect a dog clutch attached to the input shaft of a differential as the wheels are retracted; and vice versa. The system may be fitted to a steered axle or to any suitable retractable suspension system.

1. An amphibious vehicle, comprising:
 a prime mover; 
 land propulsion means; 
 marine propulsion means; 
 transmission means for transmitting power generated by the prime mover to the land and/or marine propulsion means; and 
 retractable suspension means capable of retracting and protracting the land propulsion means, wherein: 
 the suspension means and the transmission means are directly interlinked such that retraction of said land propulsion means by said suspension means actuates the transmission means to decouple the prime mover from the land propulsion means and protraction of said land propulsion means by said suspension means actuates the transmission means to couple the prime mover with the land propulsion means, wherein the transmission means is mechanically connected to the retractable suspension means and the automatic coupling and decoupling of the land propulsion means is effected by physical movement of the retractable suspension means and wherein the mechanical connection between the transmission means and the retractable suspension means is a push-pull cable. 
 
     
     
       2. An amphibious vehicle, comprising:
 a prime mover; 
 land propulsion means; 
 marine propulsion means; 
 transmission means for transmitting power generated by the prime mover to the land and/or marine propulsion means; and 
 retractable suspension means capable of retracting and protracting the land propulsion means, wherein: 
 the suspension means and the transmission means are directly interlinked such that the retraction of said land propulsion means by said suspension means actuates the transmission means to decouple the prime mover from the land propulsion means and protraction of said land propulsion means by said suspension means actuates the transmission means to couple the prime mover with the land propulsion means, wherein the transmission means is mechanically connected to the retractable suspension means and the automatic coupling and decoupling of the land propulsion means is effected by physical movement of the retractable suspension means and wherein the transmission means further comprises a spring return means. 
 
     
     
       3. An amphibious vehicle, comprising:
 a prime mover; 
 land propulsion means; 
 marine propulsion means; 
 transmission means for transmitting power generated by the prime mover to the land and/or marine propulsion means; and 
 retractable suspension means capable of retracting and protracting the land propulsion means, wherein: 
 the suspension means and the transmission means are directly interlinked such that the retraction of said land propulsion means by said suspension means actuates the transmission means to decouple the prime mover from the land propulsion means, wherein the transmission means comprises a dog clutch to effect coupling and decoupling of the land propulsion means and further comprises a spring return means which acts on the dog clutch to bias the clutch closed. 
 
     
     
       4. An amphibious vehicle, comprising:
 a prime mover; 
 land propulsion means; 
 marine propulsion means; 
 a transmission for transmitting power generated from the prime mover to the land and/or marine propulsion means; and 
 a retractable suspension capable of retracting and protracting the land propulsion means, wherein: 
 the suspension and the transmission means are directly interlinked such that retraction of said land propulsion means by said suspension actuates the transmission means to decouple the prime mover from the land propulsion means and protraction of said land propulsion means by the suspension actuates the transmission means to couple the prime mover to land propulsion means and wherein coupling and decoupling of the land propulsion means is effected by physical movement of the retractable suspension, wherein the transmission and the retractable suspension are interlinked by a push-pull cable. 
 
     
     
       5. An amphibious vehicle, comprising:
 a prime mover; 
 land propulsion means; 
 marine propulsion means; 
 a transmission for transmitting power generated from the prime mover to the land and/or marine propulsion means; and 
 a retractable suspension capable of retracting and protracting the land propulsion means, wherein: 
 the suspension and the transmission means are directly interlinked such that retraction of said land propulsion means by said suspension actuates the transmission means to decouple the prime mover from the land propulsion means and protraction of said land propulsion means by the suspension actuates the transmission means to couple the prime mover to land propulsion means and wherein coupling and decoupling of the land propulsion means is effected by physical movement of the retractable suspension wherein the transmission comprises a dog clutch to effect coupling and decoupling of the land propulsion means and wherein the transmission further comprises a return spring which acts on the dog clutch to bias the clutch closed. 
 
     
     
       6. An amphibious vehicle, comprising:
 a prime mover; 
 land propulsion means; 
 marine propulsion means; 
 a transmission for transmitting power generated by the prime mover to the land and/or marine propulsion means; and 
 a retractable suspension capable of retracting and protracting the land propulsion means, wherein: 
 the land propulsion means is automatically decoupled from the transmission when retracted by the retractable suspension means; 
 the land propulsion means is automatically coupled to the transmission when protracted by the retractable suspension means; and 
 the transmission comprises a clutch to effect coupling and decoupling of the land propulsion means and a return spring which acts on the clutch to bias the clutch closed.